Search

The existing in-mold electromagnetic stirrers (M-EMS) that are widely applied in the steel industries have experienced low efficiencies due to the high operational temperatures and open system structures. Based on simple mechanical attachments and verified by detailed 3-D electromagnetic field analyses, this paper will propose a guided field path arrangement that can enhance the overall performance of an M-EMS system by a factor of 28% in the designated stirring directions while maintaining the same energy inputs. Such evident improvements will certainly provide a valuable design and adjustment guidance for the related metal industries. Index Terms--Continuous casting process, finite-element analysis (FEA), in-mold electromagnetic stirrer, molten steel.

This paper presents an axial-flux permanent magnet (AFPM) machine with an internal coreless stator and twin external permanent magnet (PM) rotors, based on the finite-element method (FEM) by robust design, call Taguchi method to the optimum design for minimum the torque ripple and maximum the ratio between torque ripple and average torque. The optimization is realized by analyses and simulations with finite-element analysis (FEA). The design optimization process is described and the results are presented in this paper. Index Terms--Axial flux permanent magnet (AFPM), finite-element analysis (FEA), Taguchi method, torque ripple.

This paper presents the use of genetic algorithms (GAs) and the Taguchi method in optimizing an surface-mounted permanent magnet (SPM) motor for use as a fan motor in air-conditioners. GAs were used to optimize the efficiency of the motor, and the Taguchi optimization method was used and the finite-element method (FEM) analysis was conducted to compute the performance of the motor design generated by the Taguchi design of experiments. Index Terms--Cogging torque, efficiency, finite-element (FE) analysis, genetic algorithms (GAs), surface-mounted permanent magnet (SPM) motor, Taguchi optimization method.

This paper presents impacts of different permanent magnet materials and operational temperatures on the performance of interior permanent magnet (IPM) machines for electric vehicle applications. Variations of the average torque, torque ripple, cogging torque, and no-load EMF with different neodymium-iron-boron (NdFeB) permanent magnet materials and operational temperatures are investigated. Based on finite-element method (FEM), performance about the ripple and cogging torques of the IPM machine will be analyzed and some useful conclusions can be provided for researchers and engineers in the related traction motor industries. Index Terms--Cogging torque, finite-element method (FEM), interior permanent magnet (IPM) machine, torque ripple.

For stabilizing the steel-plate conveyance process, efforts on providing appropriate extra electromagnetic forces at the run-out-table of a steel mill have been extensively investigated. Such objectives can be achieved by implementing fixed poles on top of the rollers at the run-out-table to provide the controllable 2-D lift and propulsive forces, and the movable steel plate can then be driven in the desired directions. To realize the entire process, by considering the operational environment at a steel mill, an image-based online gap-detection scheme with real-time parameter calibration process has been developed. Results show that the system that is implemented with a fine-tuned interfacing/ processing scheme can supply rapid and accurate online 2-D gap profiles and, thus, fulfill the design and on-site operational objectives. Index Terms--Conveyance system, image processing, linear induction motor, optical inspection system, steel plate.

An online electromagnetic force calculation scheme, along with the appropriate closed-loop control design for driving a linear induction machine prototype, will be developed for practical industrial steel-plate conveyance system applications. Through appropriate signal detections and feedback controls, real-time balanced normal and propulsive forces can be stably generated onto the motor secondary mover (steel plate), and the objectives of noncontacting conveyance system designs and constructions can be successfully achieved. Index Terms--Conveyance system, linear induction motor, magnetic equivalent circuit, steel plate.

To achieve low-cost and high-precision operational requirements in microelectronics fabrication industry, a new microlinear switched-reluctance motor ([mu]LSRM) design that being integrated with the microelectromechanical system (MEMS) processing scheme has been investigated. With the degraded property of magnetic material after electroplating process and the geometric constraints of MEMS fabricating technology all being taken into account, the motor generated propulsive/normal force ratios at various pole shapes and winding excitation levels have been analyzed by three-dimensional finite element analysis. Results showed that the design objectives could be successfully fulfilled by the proposed [micro]LSRM structure. Index Terms-Finite-element analysis, microelectromechanical system, saturation, switched-reluctance motor.

The oscillations from Trapezoidal rule of integration following discontinuity and the one-time-step error from separate EMTP and TACS (or MODELS) simulation are the numerical stability and accuracy problems in transient study of power electronics system using EMTP. This paper presents the technique of the synchronized solution of power electronics system equations. The proposed technique implements efficient and numerically stable approaches to model the switching circuit and control system as a MODELS component. This MODELS component is connected directly to the EMTP to avoid the one-time-step delay. Therefore, the numerical oscillations and one-time-step error in standard EMTP simulation can be eliminated. Keywords: Power electronics system, EMTP, MODELS, type-94 component.

This paper, which continued the preceding works, will provide further detailed discussions about both parasitic hunting-effect alleviation of transverse flux homopolar linear induction machine (TFLIM), and improvement on closed-loop transient characteristics of transverse flux homopolar linear oscillating machine (TFLOM). Novel artificial knowledge-based compensators are proposed here to solve above problems for these time-varying and highly nonlinear machine systems. It will be shown that not only this approach is easy of practical implementation, but also the involved design tasks of such compensators are applicable for other linear machine control objectives. Illustrations and verifications will be supplied to confirm the graceful features of this intelligent strategy. Keywords: linear induction machine, linear oscillating machine, hunting effect, fuzzy logic, knowledge-based strategy.

To achieve low cost and high operational precisions in semiconductor fabrication industry, a new micro linear switched-reluctance motor ([mu]LSRM) that can be integrated with the microelectromechanical system (MEMS) processing scheme has been designed and investigated. With both the degraded material property after electroplating process and the geometric constraints of MEMS being considered, magnetic saturation characteristics of the [mu]LSRM were carefully analyzed by three-dimensional finite element analysis. Hence, the generated propulsive, normal, and guidance forces at those of the most feasible motor pole shapes and winding excitation levels can be evaluated to provide a thorough design and fabrication basis. Index Terms--Finite element analysis, microelectromechanical system, saturation, switched-reluctance motor.

This paper presents a systematic scheme to determine the optimal torque trajectory of a single-sided permanent magnet axial-flux motor (SPMAM) along with its operational constraints on both the winding currents and the speed induced voltages. Appropriate projection of the stator currents to achieve an optimal ratio of the machine propulsive/axial forces has been confirmed through detailed numerical and analytical studies. From these evaluations, a feasible operational guidance for SPMAM field-oriented control scheme realizations can be suitably provided. Index Terms--Axial force, electric vehicle, field-oriented control, finite element analysis, SPMAM.

Based on the design concepts of linear induction motors, an electromagnetic device has been constructed to investigate its feasibility for noncontacting steel-plate conveyance system application. The system is intended to provide the desired lift, propulsive, and guidance forces to the steel plate simultaneously. Three-dimensional (3-D) field distributions and force characteristics have been investigated through system state model and finite element analysis. Satisfactory results in the system's intended 3-D directions are provided to verify the suitability of the design objective. Index Terms--Conveyance system, linear induction motor, steel plate, transverse flux.

This paper is intended to investigate the electromagnetic flux distribution and side-force characteristics of a transverse flux linear switched-reluctance machine (TFLSRM) by three-dimensional finite element method. With the flux path perpendicular to its moving direction, results showed that the TFLSRM is quite suitable for high speed linear motion applications, due to the generated electromagnetic side-force which enhance the overall system guidance. From comparison analysis, conceptual design suggestions on the machine pole shapes will also be supplied. Index: pole shape, side-force, guidance, flux distribution.

This paper presents the development of a multiple reference frame that is applicable to dynamic analysis and controller design of linear electromagnetic motion devices. Orthogonal matrices and eigenvector calculations are introduced to derive these magnetically decoupled reference frames. Results show that multiple reference frame theory is quite suitable for the design and control applications associated with magnetic levitation and propulsion (MAGLEV) systems. Index: eigenvalue, eigenvector, multiple reference frame.

This paper will provide an optimal pole arrangement design scheme of a linear switched-reluctance machine that is applicable for magnetic levitated vehicle (MAGLEV) system. The proposed low-cost machine structure will be able to supply both the levitation and the propulsion forces simultaneously. Minimum torque generation and smooth switch operation in the entire operation range have been selected as the design objectives subjected to the available machine bogie and electromagnet sizes. Comparison studies on the system electromagnetic and electromechanical characteristics will be provided to verify the adequacy of the proposed design scheme.

This paper presents a linear variable-reluctance machine with magnetic-flux decoupled windings which is applicable for the automation of large scale linear propulsion system. Along with experimental investigations, a three-dimensional dynamic modelling will be provided by using Fourier expansion and state-space approach for detailed verifications.